Not trying to school you, but here is a take-
That jeep drove perfect when new. As good as any high clearance modern vehicle- any. I mean drive across the country good.
It was completely redesigned from the ground up to do that - prior to the TJ jeeps were all leaf spring suspension. They worked but had limitations.
The engineers decided to make the Jeep more people friendly. This is a machine that was born out of utility, not comfort. It took us to war and got most of us home. It traveled the world.
As of 1997, jeeps got 2 fixed axles with buckets /spring perches on on them.
They retained a ladder style truck frame and added buckets for the springs -
There are 4 springs- the frame and everything on it floats on them.
There are 4 control arms in front and rear -8 total- they control both the vertical/arc movement and axle position and pinion angle at the same time-
You have 2 more, also called track bars, that keep the axles centered as they move up and down.
As all this happens the 4 shocks dampen the movement.
2 sway bars and 4 links control excess body roll.
So what happened?
When lifted, the front axle rolls forward throwing caster out the window. The track bar pulls the axle off center and keeps it that way.
The rear axle rolls back, messing up the carefully planned pinion angle and also gets the track bar close to the gas tank skid....and, like the front, the track bar pulls the axle off center.
Typically the toe is off after all this , and the lift company includes a pitman arm with more offset assuming this corrects the relationship of the track bar and drag link the lift changed- a condition called bump steer ensues....to ice the cake the big tires all this accommodated are out of sync with the gearing- and you now have a jeep that looks cool, drives terrible and your wife has yet to see the credit card bill.
At this point, you need professional help. So you go to a shop, and they are as lost as you, they just talk more confidently and use terms you don’t know, and the results you get are a gamble at best.
And all the above is the simple version- there are different connections, bushings, etc that can be employed to lift one.
That gets you here.
A TJ specific forum. These guys should know.
What we mostly are is good group of owners who love our jeeps, make them just the vehicle we want them to be, and have a great time doing it and getting on the road and trail every chance we get.
We have different budgets, priorities and goals, but at the end of the day we know there are a number of basic things that have to happen to correct or compensate for the consequences of a lift.....and simply things that have to be right even if it is not lifted.
A TJ is not hard to get right....there are just so many ways to mess one up most owners and shops can’t sort through that to see the basics they have follow-
Good, perfectly balanced tires with 26-28 psi. Load Range C seems to stand out in comfort.
Shocks that work good for a TJ. (There really are not that many)
Caster- It doesn’t matter what you do you cannot do anything that will compensate for poor caster- there is no substitute.
Alignment- You simply have to have about 1/8 inch of toe in. Occasionally a jeep needs ball joints.
Connections- Every track bar/control arm has two ends- that is 20 connections- Plus all your steering linkage and swaybar links and shocks- Depending on what your working with you can have a nearly 50 bushings under one- None of these are there just to be there- they make connections strong but not harsh. Connections that control every thing that matters.
In addition to all the above, you have age and wear.
The purpose here is not to spout knowledge, I don’t have much - but to give you an overview that we understand the design and know how to deal with it.
If you can get some pics on here, these guys will help you. I can’t imagine owning a TJ without this forum.
Didn’t mean to write a book.
That jeep drove perfect when new. As good as any high clearance modern vehicle- any. I mean drive across the country good.
It was completely redesigned from the ground up to do that - prior to the TJ jeeps were all leaf spring suspension. They worked but had limitations.
The engineers decided to make the Jeep more people friendly. This is a machine that was born out of utility, not comfort. It took us to war and got most of us home. It traveled the world.
As of 1997, jeeps got 2 fixed axles with buckets /spring perches on on them.
They retained a ladder style truck frame and added buckets for the springs -
There are 4 springs- the frame and everything on it floats on them.
There are 4 control arms in front and rear -8 total- they control both the vertical/arc movement and axle position and pinion angle at the same time-
You have 2 more, also called track bars, that keep the axles centered as they move up and down.
As all this happens the 4 shocks dampen the movement.
2 sway bars and 4 links control excess body roll.
So what happened?
When lifted, the front axle rolls forward throwing caster out the window. The track bar pulls the axle off center and keeps it that way.
The rear axle rolls back, messing up the carefully planned pinion angle and also gets the track bar close to the gas tank skid....and, like the front, the track bar pulls the axle off center.
Typically the toe is off after all this , and the lift company includes a pitman arm with more offset assuming this corrects the relationship of the track bar and drag link the lift changed- a condition called bump steer ensues....to ice the cake the big tires all this accommodated are out of sync with the gearing- and you now have a jeep that looks cool, drives terrible and your wife has yet to see the credit card bill.
At this point, you need professional help. So you go to a shop, and they are as lost as you, they just talk more confidently and use terms you don’t know, and the results you get are a gamble at best.
And all the above is the simple version- there are different connections, bushings, etc that can be employed to lift one.
That gets you here.
A TJ specific forum. These guys should know.
What we mostly are is good group of owners who love our jeeps, make them just the vehicle we want them to be, and have a great time doing it and getting on the road and trail every chance we get.
We have different budgets, priorities and goals, but at the end of the day we know there are a number of basic things that have to happen to correct or compensate for the consequences of a lift.....and simply things that have to be right even if it is not lifted.
A TJ is not hard to get right....there are just so many ways to mess one up most owners and shops can’t sort through that to see the basics they have follow-
Good, perfectly balanced tires with 26-28 psi. Load Range C seems to stand out in comfort.
Shocks that work good for a TJ. (There really are not that many)
Caster- It doesn’t matter what you do you cannot do anything that will compensate for poor caster- there is no substitute.
Alignment- You simply have to have about 1/8 inch of toe in. Occasionally a jeep needs ball joints.
Connections- Every track bar/control arm has two ends- that is 20 connections- Plus all your steering linkage and swaybar links and shocks- Depending on what your working with you can have a nearly 50 bushings under one- None of these are there just to be there- they make connections strong but not harsh. Connections that control every thing that matters.
In addition to all the above, you have age and wear.
The purpose here is not to spout knowledge, I don’t have much - but to give you an overview that we understand the design and know how to deal with it.
If you can get some pics on here, these guys will help you. I can’t imagine owning a TJ without this forum.
Didn’t mean to write a book.
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